Jim Himes has resurrected an old LISP routine from the Cadence magazine days. This routine allows you to edit any sort of text with one command. If you are using a recent version of AutoCAD, then you may know that the built-in DDEdit command also has this capability, but there are still many people who use older versions of AutoCAD where this can come in handy.
This routine includes a DCL file to support a dialog, so you will need to place both files in a directory that is in your support file search path. Load the LISP file, then run the command DDE. You can select an attribute definition, an attribute (or a block with an attribute), text, mtext, or a dimension, and the appropriate editing command will be launched. Be careful with certain dimensions such as aligned dimensions; the dialog warns that the value shown will not be accurate.